There is a brake band adjustment procedure in the operators manual. If you don't have a manual, get the serial number from your machine, go to the Scag website, on left side there are links and one is manuals. Click on it, find your machine and serial number range, click and download the manual. When I leave my Tiger Cub in prolonged storage I leave the brake lever in the off position, this will cause the brakes to stay adjusted longer.
To adjust the brake, the rear wheels have to be removed. There are few spots where the machine can be jacked up under the rear. I cut up some wood blocks from a 6 by 6 on my band saw to fit under both sides of the machine so I can get the jack out of my way and remove the rear wheels to do a brake adjustment. Both rear wheels need to off at the same time to do this adjustment correctly.
Mad Mackie in CT